Compilare: main.cpp: In function 'void solve_test()': main.cpp:127:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(edges.size() != N - 1) ~~~~~~~~~~~~~^~~~~~~~ main.cpp:85:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &N, &M); ^ main.cpp:99:36: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &x, &y, &z); ^ main.cpp: In function 'int main()': main.cpp:159:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("revolve.in", "r", stdin); ^ main.cpp:160:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("revolve.out", "w", stdout); ^ main.cpp:164:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &T); ^